My Brother In Law has a set of ADL 300i auto speakers, and he wanted to see if they would still work. They only have the spring clips, so could not use my regular cables, so I grabbed a roll of zip cord speaker cable I had on the shelf to hook them into my shop system, just to test them. Here is the roll of 14/2 speaker cable that as you can see was manufactured in Sept. 2009. That's just under 3 years ago.When you strip this wire, here is what you get. Copper has corroded and is no longer nice and shiny. This is not the old end of the cable, but a section taken from about 6' in.